I'm getting condensation in my headlight assembly, Is this an easy fix? on 2006 Cadillac STS

I've tried to find the source of how water is getting inside the assembly, & can't get it to evaporate, no luck so far. Will the headlight assembly need replaced? & How much? if so.

Asked by for the 2006 Cadillac STS
yes it needs replacing soon. the dealer has the parts but will be costly. try